This study was performed to describe the extraforaminal approach of biportal endoscopic spinal surgery (BESS) as a new endoscopic technique for transforaminal decompression and discectomy and to demonstrate the clinical outcomes of this new procedure for the first time. Twenty-one patients (27 segments) who underwent the extraforaminal approach of BESS between March 2015 and April 2016 were enrolled according to the inclusion and exclusion criteria. The operative time (minutes/level) and complications after the procedure were recorded. The visual analog scale (VAS) score was checked to assess the degree of radicular leg pain preoperatively and at the time of the last follow-up. The modified Macnab criteria were used to examine the clinical outcomes at the time of the last follow-up. The mean duration of the follow-up period was 14.8 months (minimum duration 12 months). The mean operative time was 96.7 minutes for one level. The mean VAS score for radicular leg pain dropped from a preoperative score of 7.5 ± 0.9 to a final follow-up score of 2.5 ± 1.2 (p < 0.001). The final outcome according to the modified Macnab criteria was excellent in 5 patients (23.8%), good in 12 (57.2%), fair in 4 (19.0%), and poor in 0. Therefore, excellent or good results (a satisfied outcome) were obtained in 80.9% of the patients. Complications were limited to one dural tear (4.8%). The authors found that the extraforaminal approach of BESS was a feasible and advantageous endoscopic technique for the treatment of foraminal lesions, including stenosis and disc herniation. They suggest that this technique represents a useful, alternative, minimally invasive method that can be used to treat lumbar foraminal stenosis and disc herniation.
Jae-Sung Ahn, Ho-Jin Lee, Dae-Jung Choi, Ki-young Lee and Sung-jin Hwang
Ki Young Lee, Jung-Hee Lee, Kyung-Chung Kang, Won-Ju Shin, Sang Kyu Im and Seong Jin Cho
The incidence of proximal junctional kyphosis (PJK) after long-segment fixation in patients with adult spinal deformity (ASD) has been reported to range from 17% to 61.7%. Recent studies have reported using “hybrid” techniques in which semirigid fixation is introduced between the fused and flexible segments at the proximal level to allow a more gradual transition. The authors used these hybrid techniques in a clinical setting and analyzed PJK to evaluate the usefulness of the flexible rod (FR) technique.
The authors retrospectively selected 77 patients with lumbar degenerative kyphosis (LDK) who underwent sagittal correction and long-segment fixation and had follow-up for > 1 year. An FR was used in 30 of the 77 patients. PJK development and spinal sagittal changes were analyzed in the FR and non-FR groups, and the predictive factors of PJK between a PJK group and a non-PJK group were compared.
The patient population comprised 77 patients (75 females and 2 males) with a mean (± SD) follow-up of 32.0 ± 12.7 months (36.7 ± 9.8 months in the non-FR group and 16.8 ± 4.7 months in the FR group) and mean (± SD) age of 71.7 ± 5.1 years. Sagittal balance was well maintained at final follow-up (10.5 and 1.5 mm) in the non-FR and FR groups, respectively. Thoracic kyphosis (TK) and lumbar lordosis (LL) were improved in both groups, without significant differences between the two (p > 0.05). PJK occurred in 28 cases (36.4%) in total, 3 (10%) in the FR and 25 (53.2%) in the non-FR group (p < 0.001). Postoperatively, PJK was observed at an average of 8.9 months in the non-FR group and 1 month in the FR group. No significant differences in the incidence of PJK regarding patient factors or radiological parameters were found between the PJK group and non-PJK group (p > 0.05). However, FR (vs non-FR) and interbody fusion except L5–S1 using oblique lumbar interbody fusion (vs non–oblique lumbar interbody fusion), demonstrated a significantly lower PJK prevalence (p < 0.001 and p = 0.044) among the surgical factors.
PJK was reduced after surgical treatment with the FR in the patients with LDK. Solid long-segment fixation and the use of the FR may become another surgical option for spine surgeons who plan and make decisions regarding spine reconstruction surgery for patients with ASD.
Jaechan Park, Wonsoo Son, Ki-Su Park, Min Young Kim and Joomi Lee
The Ghajar Guide technique is used to direct a ventricular catheter at a 90° angle to the skull surface at Kocher’s point. However, the human calvaria is not completely spherical. Lateral to the sagittal midline, the calvaria slopes downward with individual variation and thereby affects the accuracy of ventricular catheter placement. Accordingly, the authors investigated the accuracy of the orthogonal catheter trajectory using radiographic simulation and examined the effect of the calvarial slope on this accuracy.
A catheter trajectory orthogonal to the skull surface at Kocher’s point and the ideal catheter trajectory to the foramen of Monro were drawn bilaterally on coronal head images of 52 patients with hydrocephalus. The correction angle, the difference between the 2 catheter trajectories, was then measured. Meanwhile, the calvarial slope was measured around Kocher’s point by using a coronal head image. The correlation between the correction angle and factors such as the calvarial slope and bicaudate index was then assessed using a Pearson correlation analysis.
The ventricular catheter trajectory orthogonal to the skull at Kocher’s point in the patients with hydrocephalus led to a catheter trajectory into the ipsilateral (70.2%) or contralateral (29.8%) lateral ventricles. The correction angles ranged from −3.3° to 16.4° (mean ± SD 5.7° ± 3.7°). In 87 (83.7%) head sides, lateral deviation from the orthogonal trajectory was required to approximate the ideal trajectory, and the correction angle ranged from 2.0° to 16.4° (mean 6.7° ± 2.9°). The calvarial slope in the 104 head sides ranged from 15.6° to 32.5° (mean 24.2° ± 3.1°). Pearson correlation analysis revealed a strong positive correlation (r = 0.733) between the calvarial slope and the correction angle.
The accuracy of ventricular catheter placement using the Ghajar Guide technique is affected primarily by the calvarial slope around Kocher’s point. A radiographic analysis of a preoperative coronal head image can be used to estimate the accuracy of ventricular catheter placement and enable adjustment to approximate the ideal catheter trajectory.
Yong Hun Pee, Ki Joon Kim, Young-Geun Choi, Sang Hyeop Jeon, Jong Dae Park and Sang-Ho Lee
✓ In this report, the authors present the case of patient with a lymphocele in the retroperitoneal area following anterior lumbar interbody fusion at L4–5. A lymphocele is a rare complication of spinal operations, especially lower lumbar spinal surgeries. The authors discuss this complicating factor and describe its features and treatments.
Young-Hoon Kim, Young Jin Lee, Jung Ho Han, Soyeon Ahn, Jaebong Lee, Jae Hyoung Kim, Byung Se Choi, Jae Seung Bang, Chae-Yong Kim, Gyojun Hwang, O-Ki Kwon and Chang Wan Oh
The authors aimed to assess whether the prevalence of intracranial aneurysms in patients with intracranial meningiomas was higher than that in a healthy population.
The authors performed a hospital-based case-control study of 300 patients with newly diagnosed intracranial meningiomas and 900 age- and sex-matched controls without a history of brain tumors to evaluate any associations between intracranial aneurysms and intracranial meningiomas. Unconditional multivariate logistic regression models were used for case-control comparisons.
Intracranial aneurysms were identified in 23 patients (7.7%) and 24 controls (2.7%; p < 0.001). There was a significant association between intracranial aneurysms and intracranial meningiomas (OR 2.913, 95% CI 1.613–5.261) and hypertension (OR 1.905, 95% CI 1.053–3.446). In a subgroup analysis of the patients with newly diagnosed intracranial meningiomas, there was a significant association between intracranial aneurysms and hypertension (OR 2.876, 95% CI 1.125–7.352) and tumor volume (OR 1.012, 95% CI 1.001–1.024). These patients were also more likely than controls to have other intracranial vascular diseases (p < 0.001), such as isolated occlusion of the intracranial vessels, excluding intracranial aneurysms.
The prevalence of intracranial aneurysms was higher in patients with intracranial meningiomas. Hypertension and tumor volume appear to be associated with the formation of intracranial aneurysms in these patients.
Seung-Ki Kim, Kyu-Chang Wang, Byung-Kyu Cho, Hyun-Tai Chung, Young-Yim Kim, Su-Young Lim, Choon-Taek Lee and Hyun Jib Kim
Object. Multiple gene replacements have been examined as a potential treatment modality for malignant gliomas. Nevertheless, no reports are available that detail the synergy, additivity, or antagonism of multiple genes. The aim of this study was to assess the interaction between p53 and p16 genes in the growth of glioma cell lines.
Methods. The human glioma cell lines U87MG and U373MG were transduced using an adenoviral vector with Ad-p53, Ad-p16, or both. Western blotting was performed to determine the expression of the protein products of the transduced p53 and p16 genes. To establish whether the combination of Ad-p53 and Ad-p16 would be beneficial, the effects of gene combinations at the median inhibitory concentration level were analyzed using the isobologram method. Annexin assays and cell cycle analyses were performed on the transduced cells. Western blotting demonstrated the expression of p53 and p16 in transduced cells. Simultaneous exposure to Ad-p53 and Ad-p16 produced additive effects in both glioma cell lines. Experimental data points in U373MG lay near the Mode I line, indicating that the vectors had a different mode of action. The restoration of normal p53-encoded protein in the mutant cell lines induced apoptosis, whereas in the wild-type p53 cell lines, the overexpression of wild-type p53 resulted in a moderate degree of apoptosis and G1 arrest. Furthermore, Ad-p16 induced more marked G1 arrest than Ad-p53 in cells with wild-type p53.
Conclusions. The results show that interaction between Ad-p53 and Ad-p16 is additive, regardless of p53 gene status.
Ji Yeoun Lee, Young Ah Lee, Hae Woon Jung, Sangjoon Chong, Ji Hoon Phi, Seung-Ki Kim, Choong-Ho Shin and Kyu-Chang Wang
Due to their distinct location, suprasellar arachnoid cysts are known to cause a wide variety of problems, such as hydrocephalus, endocrine symptoms, and visual abnormalities. The long-term outcome of these cysts has not been elucidated. To find out the long-term outcome of suprasellar arachnoid cysts, a retrospective review of the patients was performed. The neurological and endocrine symptoms were thoroughly reviewed.
Forty-five patients with suprasellar arachnoid cysts, with an average follow-up duration of 9.7 years, were enrolled in the study. A comprehensive review was performed of the results of follow-up regarding not only neurological symptoms but also endocrine status. The outcomes of 8 patients who did not undergo operations and were asymptomatic or had symptoms unrelated to the cyst were included in the series.
Surgery was most effective for the symptoms related to hydrocephalus (improvement in 32 of 32), but endocrine symptoms persisted after surgery (4 of 4) and required further medical management. More surprisingly, a fairly large number of patients (14 of 40; 1 was excluded because no pre- or postoperative endocrine evaluation was available) who had not shown endocrine symptoms at the time of the initial diagnosis and treatment later developed endocrine abnormalities such as precocious puberty and growth hormone deficiency. The patients with endocrine symptoms detected during the follow-up included those in both the operated (n = 12 of 32) and nonoperated (n = 2 of 8) groups who had been stable during follow-up since the initial diagnosis.
This study implies that patients with suprasellar arachnoid cysts can develop late endocrine problems during follow-up, even if other symptoms related to the cyst have been successfully treated. Hence, patients with these cysts need long-term follow-up for not only neurological symptoms but also endocrine abnormalities.
Yong-Jun Cho, Chi Hern Lee, Dae Won Kim, Ki-Yeon Yoo, Won Sik Eum, Min Jea Shin, Hyo Sang Jo, Jinseu Park, Kyu Hyung Han, Keun Wook Lee and Soo Young Choi
The authors investigated the effects of a silk solution against laminectomy-induced dural adhesion formation and inflammation in a rat model. They found that it significantly reduced postlaminectomy dural adhesion formation and inflammation. Dural adhesion formation, thought to be an inevitable consequence of laminectomy, is one of the most common complications following spinal surgery, and the authors' results indicate that the silk solution might be a potential novel therapeutic agent for dural adhesion formation.
Kyung-Ho Park, Jaeho Lee, Chul-Gyu Yoo, Young Whan Kim, Sung Koo Han, Young-Soo Shim, Seung-Ki Kim, Kyu-Chang Wang, Byung-Kyu Cho and Choon-Taek Lee
Object. Malignant glioma could be an ideal candidate for local gene therapy because its invasion is local and it has little metastatic potential. A low expression level and high degradation activity of p27 are known to constitute an independent poor prognostic factor in patients with malignant glioma. In this study, the authors investigated the roles of wild-type p27 and mutant p27 on the treatment of malignant glioma.
Methods. The authors used two adenoviruses: one expressed wild-type p27 (ad-p27wt) and the other, containing a mutation at the major metabolic site, expressed mutant p27 (ad-p27mt). The antitumor effects of the two adenoviruses were compared with respect to cell growth arrest, cell cycle alteration, apoptosis induction, and in vitro tumorigenicity in three glioblastoma mutiforme (GBM) cell lines and in a primary GBM cell line. Transduction with ad-p27wt or ad-p27mt induced the production of p27 and the dephosphorylation of pRB. The protein level of mutant p27 was significantly higher than that of wild-type p27. The ad-p27wt induced cell cycle arrest at the G1—S transition point, whereas the ad-p27mt induced arrest at the G2—M point. Both ad-p27wt and ad-p27mt induced a growth-inhibiting effect, apoptosis, and suppression of in vitro tumorigenicity; however, ad-p27mt displayed a stronger antitumor effect than ad-p27wt in brain tumor cell lines.
Conclusions. Gene therapy involving p27, especially mutant p27, has the potential to become a novel and powerful therapy for malignant glioma.
Hyun-Seung Kang, Youn-Joo Moon, Young-Yim Kim, Woong-Yang Park, Ae Kyung Park, Kyu-Chang Wang, Jeong Eun Kim, Ji Hoon Phi, Ji Yeoun Lee and Seung-Ki Kim
Moyamoya disease (MMD) is a cerebrovascular occlusive disease affecting bilateral internal carotid termini. Smooth-muscle cells are one of the major cell types involved in this disease process. The characteristics of circulating smooth-muscle progenitor cells (SPCs) in MMD are poorly understood. The authors purified SPCs from the peripheral blood of patients with MMD and sought to identify differentially expressed genes (DEGs) in SPCs from these patients.
The authors cultured and isolated SPCs from the peripheral blood of patients with MMD (n = 25) and healthy control volunteers (n = 22). After confirmation of the cellular phenotype, RNA was extracted from the cells and DEGs were identified using a commercially available gene chip. Real-time quantitative reverse transcription polymerase chain reaction was performed to confirm the putative pathogenetic DEGs.
The SPC-type outgrowth cells in patients with MMD invariably showed a hill-and-valley appearance under microscopic examination, and demonstrated high α–smooth muscle actin, myosin heavy chain, and calponin expression (96.5% ± 2.1%, 42.8% ± 18.6%, and 87.1% ± 8.2%, respectively), and minimal CD31 expression (less than 1%) on fluorescence-activated cell sorter analysis. The SPCs in the MMD group tended to make more irregularly arranged and thickened tubules on the tube formation assay. In the SPCs from patients with MMD, 286 genes (124 upregulated and 162 downregulated) were differentially expressed; they were related to cell adhesion, cell migration, immune response, and vascular development.
With adequate culture conditions, SPCs could be established from the peripheral blood of patients with MMD. These cells showed specific DEGs compared with healthy control volunteers. This study provides a novel experimental cell model for further research of MMD.